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For electric vehicles the ability for regenerative braking reduces the use of friction brakes. Particularly on the rear axle of vehicles with reduced dynamic requirements such as urban vehicles, this can offer a potential for downsizing or, in extreme cases, even the elimination of the friction brakes on the rear axle. Due to the fact that the rear axle service brakes also represent the typical parking brake location in SoA (State-of-Art) vehicles, a rigorous rethinking of the parking brake concept is necessary to incorporate safe vehicle standstill management for such novel brake system topology. This research study introduces a novel parking brake design that covers SoA but also legal requirements while retaining potentials associated with the elimination of the rear service brakes such as cost and packaging.

India contributed to 11% of the global road accidents and was ranked 1st among road deaths according to the latest World Health Organization (WHO) report 2018. Indian National Highways (NH) is a meagre 5% of the country’s road network but accounts for 55% of the road accidents and 61% of the road deaths. Majority of the freight traffic is ferried by Commercial Vehicles (CV) or trucks along these highways and this in turn increases the probability of them being involved in a road accident. The country’s economy is forecasted to thrive in the coming years and hence the requirement of CVs is aligned to international categorisation in the supply chain and shall play a pivotal role. In the year 2019, 13,532 road deaths were associated with CV occupants. The trucking industry is an unorganized sector wherein the illegal overloading of vehicles and over-the-limit driving hours pose a serious threat to road users.

Software-in-the-Loop (SiL) test environments are the ideal virtual platforms for enabling continuous-development, -integration, -testing -delivery or -deployment commonly referred as Continuous-X (CX) of the complex functionalities in the current automotive industry. This trend especially is contributed by several factors such as the industry wide standardization of the model exchange formats, interfaces as well as architecture definitions. The approach of frontloading software testing with SiL test environments is predominantly advocated as well as already adopted by various Automotive OEMs, thereby the demand for innovating applicable methods is increasing. However, prominent usage of the existing monolithic architecture for interaction of various elements in the SiL environment, without regarding the separation between functional and non-functional test scope, is reducing the usability and thus limiting significantly the cost saving potential of CX with SiL.

Safety-critical embedded software has to satisfy stringent quality requirements. One such requirement, imposed by all contemporary safety standards, is that no critical run-time errors must occur. Runtime errors can be caused by undefined or unspecified behavior of the programming language; examples are buffer overflows or data races. They may cause erroneous or erratic behavior, induce system failures, and constitute security vulnerabilities. A sound static analyzer reports all such defects in the code, or proves their absence. Sound static program analysis is a verification technique recommended by ISO/FDIS 26262 for software unit verification and for the verification of software integration. In this article we propose an analysis methodology that has been implemented with the static analyzer Astrée. It supports quick turn-around times and gives highly precise whole-program results.

A major source for soot particle formation in Gasoline-Direct-Injection (GDI) engines are fuel-rich zones near walls as a result of wall wetting during injection. To address this problem, a thorough understanding of the wall film formation and evaporation processes is necessary. The wall temperature before, during and after fuel impingement is an important parameter in this respect, but is not easily measured using conventional methods. In this work, a recently developed laser-based phosphor thermography technique is implemented for investigations of spray-induced surface cooling. This spatially and temporally resolved method can provide surface temperature measurements on the wetted side of the surface without being affected by the fuel-film. Zinc oxide (ZnO) particles, dispersed in a chemical binder, were deposited onto a thin steel plate obtaining a coating thickness of 17 μm after annealing.

As automobiles become increasingly smarter, the need to understand within the automotive software the physical behavior of its parts is growing as well. The laws of physics governing such behavior are mostly formulated as differential equations, which today are usually created or obtained from various modeling tools. For solving them, the tools offer several solvers to satisfy the requirements of different problems. E.g. simple and fast explicit low order solvers for non-stiff problems and more complex implicit solvers for stiff problems. Though the modeling and code generation features as available in such tools are desirable for embedded automotive software, they cannot be used directly due to special restrictions with respect to hard realtime constraints. One such restriction is the organization of automotive software in components complying with the AUTOSAR standard which is not widely supported by the modeling tools.

The Side View Assist is the World’s first rider assistance system for two-wheelers. This is a Blind Spot Warning system, which uses four ultrasonic sensors to monitor the surrounding of the rider. Whenever there is a vehicle (i.e. a car, truck, or another motorbike) in the rider’s blind spot, the technology warns the rider with an optical signal close to the mirror. This will allow the rider to avoid a collision when changing lanes. In the current vehicle application, Side View Assist is active at speeds ranging from 25 to 80 kilometers per hour and supports riders whenever the difference in relative speed to other road users is small. The system helps to improve safety especially in cities, where heavy traffic makes it necessary to change lanes more often. Originally such systems have been developed for cars and different system solutions for cars have been in serial production for several years. The challenge was to adapt these systems so they would work for two-wheelers as well.

Many software functions currently available in the engine control units have been developed for several years (decades in some cases), reengineered or adapted due to new requirements, what may add to their inherent complexity an unnecessary complication. This paper deals with the study and implementation of a software reengineering strategy for the embedded domain, which is in transfer from research department to product development, here applied to improve maintainability of flex fuel functions. The strategy uses the SCODE “Essential Analysis”, an approach for the embedded system domain. The method allows to reduce the system complexity to the unavoidable inherent problem complexity, by decomposing the system into smaller sub problems based on its essential physics. A case study was carried out to redesign a function of fuel adaptation. The analysis was performed with the support of a tool, which covers all the phases of the method.

Current exhaust gas emission regulations can only be well adhered to through optimal interplay of combustion engine and exhaust gas after-treatment systems. Combining a modern diesel engine with several exhaust gas after-treatment components (DPF, catalytic converters) leads to extremely complex drive systems, with very complex and technically demanding control systems. Current engine ECUs (Electronic Control Unit) have hundreds of functions with thousands of parameters that can be adapted to keep the exhaust gas emissions within the given limits. Each of these functions has to be calibrated and tested in accordance with the rest of the ECU software. To date this task has been performed mostly on engine test benches or in Hardware-in-the-Loop (HiL) setups. In this paper, a Software-in-the-Loop (SiL) approach, consisting of an engine model and an exhaust gas treatment (EGT) model, coupled with software from a real diesel engine ECU, will be described in detail.

AUTOSAR (AUTomotive Open System ARchitecture) is a worldwide standard for automotive basic software in line with an architecture that eases exchange and transfer of application software components between platforms or companies. AUTOSAR provides the standardized architecture together with the specifications of the basics software along with the methodology for developing embedded control units for automotive applications. AUTOSAR matured over the last several years through intensive development, implementation and maintenance. Two main releases (R3.2 and R4.0) represent its current degree of maturity. AUTOSAR is driven by so called core partners: leading car manufacturers (BMW, Daimler, Ford, GM, PSA, Toyota, Volkswagen) together with the tier 1 suppliers Continental and Bosch. AUTOSAR in total has more than 150 companies (OEM, Tier X suppliers, SW and tool suppliers, and silicon suppliers) as members from all over the world.

A new high-performance interchip interface, called Serial WireRing, is introduced. It combines technically mature and established methods, whereby Serial WireRing provides a simple, robust and very inexpensive solution to replace the Serial Peripheral Interface (SPI). Serial WireRing uses a daisy chain ring topology, realized by unidirectional point-to-point connections from device to device. Serial WireRing is realized by a simple “wire ring” with CMOS, LVDS, optical or any other suitable signaling, even mixed. Therefore it has a very low pin count. In order to minimize the latency each slave transmits the data that it receives with 1 bit delay only. In order to avoid clock/data skew, the serial data and clock are merged into one bitstream. A corresponding clock is extracted at each receiver by a clock and data recovery circuit, driven by a simple internal oscillator.

Environmental consciousness and tightening emissions legislation push the market share of electronic fuel injection within a dynamically growing world wide small engines market. Similar to automotive engines during late 1980's, this opens up opportunities for original equipment manufacturers (OEM) and suppliers to jointly advance small engines performance in terms of fuel economy, emissions, and drivability. In this context, advanced combustion system analyses from automotive engine testing have been applied to a typical production motorcycle small engine. The 125cc 4-stroke, 2-valve, air-cooled, single-cylinder engine with closed-loop lambda-controlled electronic port fuel injection was investigated in original series configuration on an engine dynamometer. The test cycle fuel consumption simulation provides reasonable best case fuel economy estimates based on stationary map fuel consumption measurements.

This study presents measurements of transient flow field and spray structures inside an optically accessible DISI (direct-injection spark-ignition) internal combustion engine. The flow field has a direct effect upon mixture and combustion processes. Given the need to increase the efficiency and performance of modern IC engines and thus reduce emissions a detailed understanding of the flow field is necessary. The method of choice was high-speed two-component particle image velocimetry (PIV) imaging a large field of view (43 x 44 mm₂). To capture the temporal evolution of the main flow features the repetition rate was set to 6 kHz which resolves one image per 1° crank angle (CA) at 1000 rpm. The crank angle range recorded was the latter half of the compression stroke at various engine speeds as well as various charge motions (neutral, tumble and swirl). Moreover, consecutive cycles were recorded allowing a detailed investigation of cycle-to-cycle variations.

In order to master the increasing complexity of electrical/electronic (E/E) systems in vehicles, E/E architecture design has become an established discipline. The task of the E/E architecture design is to come up with solutions to challenging and often contradictory requirements such as reduced cost and increased flexibility / scalability. One way to optimize the E/E architecture in terms of cost (electronics & wiring harness) is to integrate functions. This can be done by either combining functions from multiple ECUs into a single ECU or by introducing Domain Control Units. Domain Control Units provide the main software functionality for a vehicle domain, while relegating the basic functions of actuator control to connected intelligent actuators. Depending on the different market segments (low price, volume and premium) and the different vehicle domains, the actual usage of Domain Control Units can be quite different and sometimes questionable.

The reduction of nitrous oxides in the exhaust gases of internal combustion engines using a urea water solution is gaining more and more importance. While maintaining the future exhaust gas emission regulations, like the Euro 6 for passenger cars and the Euro 5 for commercial vehicles, urea dosing allows the engine management to be modified to improve fuel economy as well. The system manufacturer Robert Bosch has started early to develop the necessary dosing systems for the urea water solution. More than 300.000 Units have been delivered in 2007 for heavy duty applications. Typical dosing quantities for those systems are in the range of 0.01 l/h for passenger car systems and up to 10 l/h for commercial vehicles. During the first years of development and application of urea dosing systems, instantaneous flow measuring devices were used, which were not operating fully satisfactory.

1 High precision high pressure diesel common rail fuel injection systems play a key role in emission control, fuel consumption and driving performance. Deposits have been observed on internal injector components, for example in the armature assembly, in the slots of the piston and on the nozzle needle. The brownish to colourless deposits can adversely impact driveability and result in non-compliance with the Euro 4 or Euro 5 emission limits. The deposits have been extensively studied to understand their composition and their formation mechanism. Due to the location of these deposits, the influence of combustion gas can be completely ruled out. In fact, their formation can be explained by interactions of certain diesel fuel additives, including di- and mono-fatty acids. This paper describes the methodology used and the data generated that support the proposed mechanisms. Moreover, approaches to avoid such interactions are discussed.

Electromagnetic Compatibility (EMC) requirements and the effort to fulfill them are increasing steadily in automotive applications. This paper demonstrates the usage of virtual prototyping to efficiently investigate the EMC behavior of a gasoline direct injection system. While the system worked functionally as designed, tests indicated that current and especially future client-specific EMC limits could not be met. The goal of this investigation was to identify and eliminate the cause of EMC emissions using a virtual software prototype including the controller ASIC, boost converter, pi filter, injection valves and wire harness. Applying virtual prototyping techniques it was possible to capture the motor control system in a simulation model which reproduced EMC measurements in the frequency ranges of interest.

This paper describes the first results from the AutoMoDe project (Automotive Model-based Development), where an integrated methodology for model-based development of automotive control software is being developed. The results presented include a number of problem-oriented graphical notations, based on a formally defined operational model, which are associated with system views for various degrees of abstraction. It is shown how the approach can be used for partitioning comprehensive system designs for subsequent implementation-related tasks. Recent experiences from a case study of an engine management system, specific issues related to reengineering, and the current status of CASE-tool support are also presented.

The amount of software integrated into today's vehicles growths exponential and tends to be a patchwork of non interrelated applications. However the interrelationship gets more and more intensive as applications start to cooperate and therefore communicate with each other. By introducing a domain exceeding middleware concept we want applications to experience a high level of integration and enable outsourcing of features applications have in common.

The development of future automotive electronic systems requires new concepts in the software architecture, development methodology and information exchange. At Bosch an XML and MSR based technology is applied to achieve a consistent information handling throughout the entire software development process. This approach enables the tool independent exchange of information and documentation between the involved development partners. This paper presents the software architecture, the specification of software components in XML, the process steps, an example and an exchange scenario with an external development partner.